1. Technical Field
The invention relates to a liquid crystal-containing composition used for display devices, image/information recording devices, spatial light modulators, and the like, a method for producing the same, and a crystal display device including the same.
2. Background Art
In recent years, cholesteric liquid crystal display devices are receiving much attention due to their characteristics such as retention of a display with no power, high brightness of a display by disuse of a polarizing plate, and achievement of a color display without use of a color filter.
In particular, a cholesteric liquid crystal is composed of rod-like molecules disposed spirally, and interferes with and reflects light corresponding to the spiral pitch thereof (referred to as selective reflection). Therefore, when the spiral pitch has a size corresponding to the wavelengths of red, green, and blue colors, a vivid color display is provided without a color filter.
For example, a cholesteric liquid crystal filled in a cell composed of a pair of substrates each having an electrode is known to assume two alignment states: planar (P) alignment and focal conic (F) alignment. The P alignment is a state in which the spiral axis is aligned perpendicular to the substrate surface, and causes selective reflection. The F alignment is a state in which the spiral axis is aligned in parallel with the substrate surface, and transmits light. The two alignment states are changed each other when a voltage is applied between the electrodes.
Therefore, when a light absorber, for example, a black color, is disposed on the back of the cell, a bright display giving a selective reflection color is provided under the P alignment state, and a dark display giving a black color of the light absorber is provided under the F alignment state. Of the above-described alignment states, the P and F alignment states are stably retained with no power. Utilizing the property, a memory display which retains its display with no power is realized.
Various liquid crystal display devices including a cholesteric liquid crystal are proposed in several documents.